added healthcheck for the admin ui

Author: greyWizardCode

ECommerce.AdminUI/ECommerce.AdminUI.csproj

@@ -1,12 +1,14 @@
 <Project Sdk="Microsoft.NET.Sdk.Web">
-  
+
   <PropertyGroup>
     <TargetFramework>net8.0</TargetFramework>
     <Nullable>enable</Nullable>
     <ImplicitUsings>enable</ImplicitUsings>
   </PropertyGroup>
-  
+
   <ItemGroup>
+    <PackageReference Include="prometheus-net" Version="8.0.1" />
+    <PackageReference Include="prometheus-net.AspNetCore" Version="8.0.1" />
     <PackageReference Include="System.IdentityModel.Tokens.Jwt" Version="8.12.0" />
   </ItemGroup>
 

ECommerce.AdminUI/Program.cs

@@ -1,3 +1,6 @@
+using Prometheus;
+using Microsoft.AspNetCore.Diagnostics.HealthChecks;
+
 var builder = WebApplication.CreateBuilder(args);
 
 // Log all environment variables to help with debugging
@@ -13,6 +16,9 @@
 Console.WriteLine($"TokenServiceUrl from config: {builder.Configuration["TokenServiceUrl"] ?? "not set"}");
 Console.WriteLine("==========================");
 
+// Add Prometheus metrics
+builder.Services.AddHealthChecks();
+
 // Add services to the container.
 builder.Services.AddRazorPages()
     .AddMvcOptions(options =>
@@ -88,6 +94,7 @@
     app.UseHsts();
 }
 
+// Add Prometheus metrics endpoint
 app.UseHttpsRedirection();
 app.UseStaticFiles();
 
@@ -96,6 +103,11 @@
 
 app.UseAuthorization();
 
+// Configure metrics endpoint before mapping controllers
+app.UseMetricServer("/metrics"); // This exposes the metrics endpoint
+app.UseHttpMetrics(); // Collect HTTP metrics
+
 app.MapRazorPages();
+app.MapHealthChecks("/health");
 
 app.Run();

ECommerce.AdminUI/k8s/overlays/dev/configmap.yaml

@@ -3,6 +3,6 @@ kind: ConfigMap
 metadata:
   name: admin-ui-config
 data:
-  ModularMonolithApiUrl: "http://dev-modularmonolith:8080/modulith"
-  TokenServiceUrl: "http://dev-modularmonolith:8080"
+  ModularMonolithApiUrl: "http://modularmonolith:8080/modulith"
+  TokenServiceUrl: "http://modularmonolith:8080"
 

ECommerce.AdminUI/k8s/overlays/dev/kustomization.yaml

@@ -4,7 +4,7 @@ kind: Kustomization
 resources:
 - ../../base
 
-namePrefix: dev-
+#namePrefix: dev-
 
 replicas:
 - name: admin-ui

ECommerce.AdminUI/k8s/servicemonitor.yaml

@@ -0,0 +1,19 @@
+apiVersion: monitoring.coreos.com/v1
+kind: ServiceMonitor
+metadata:
+  name: admin-ui
+  labels:
+    app: admin-ui
+    release: prometheus  # Ensure this matches your Prometheus operator labels
+spec:
+  selector:
+    matchLabels:
+      app: admin-ui
+  endpoints:
+  - port: http  # Changed from targetPort: 8080 to port: http to match the service port name
+    interval: 30s
+    path: /metrics
+    scheme: http
+  namespaceSelector:
+    matchNames:
+      - default

ECommerceApp/ECommerceApp.csproj

@@ -16,6 +16,7 @@
     </PackageReference>
     <PackageReference Include="Microsoft.Extensions.Configuration" Version="8.0.0" />
     <PackageReference Include="Microsoft.Extensions.Logging" Version="8.0.1" />
+    <PackageReference Include="prometheus-net.AspNetCore" Version="8.2.1" />
     <PackageReference Include="Swashbuckle.AspNetCore" Version="6.9.0" />
   </ItemGroup>
 

ECommerceApp/Program.cs

@@ -13,6 +13,7 @@
 using Microsoft.AspNetCore.Authentication.JwtBearer;
 using Microsoft.IdentityModel.Tokens;
 using Microsoft.OpenApi.Models;
+using Prometheus;
 
 namespace ECommerceApp;
 
@@ -81,6 +82,9 @@ public static async Task  Main(string[] args)
 
         var app = builder.Build();
 
+        // Enable Prometheus metrics
+        app.UseHttpMetrics();
+
         // Log ASPNETCORE_PATHBASE value at startup
         var logger = app.Logger;
         var pathBase = app.Configuration["ASPNETCORE_PATHBASE"] ?? Environment.GetEnvironmentVariable("ASPNETCORE_PATHBASE");
@@ -114,6 +118,9 @@ public static async Task  Main(string[] args)
             });
         }
 
+        // Expose /metrics endpoint for Prometheus
+        app.MapMetrics();
+
         await BusinessEventsModule.InitializeDefaultSchemasAsync(app.Services);
 
         // After builder.Build():

ECommerceApp/k8s/service.yaml

@@ -2,11 +2,14 @@ apiVersion: v1
 kind: Service
 metadata:
   name: modularmonolith
+  labels:
+    app: modularmonolith  # This label is crucial for ServiceMonitor discovery
 spec:
   type: ClusterIP
   selector:
     app: modularmonolith
   ports:
-    - protocol: TCP
+    - name: http
+      protocol: TCP
       port: 8080
       targetPort: 8080

ECommerceApp/k8s/servicemonitor.yaml

@@ -0,0 +1,19 @@
+apiVersion: monitoring.coreos.com/v1
+kind: ServiceMonitor
+metadata:
+  name: modularmonolith
+  labels:
+    app: modularmonolith
+    release: prometheus  # Ensure this matches your Prometheus operator labels
+spec:
+  selector:
+    matchLabels:
+      app: modularmonolith
+  endpoints:
+  - targetPort: 8080
+    interval: 30s
+    path: /metrics
+    scheme: http
+  namespaceSelector:
+    matchNames:
+      - default

Tiltfile

@@ -29,6 +29,7 @@ k8s_yaml([
     'ECommerceApp/k8s/service.yaml',
     'ECommerce.DatabaseMigrator/k8s/db-connection-sealedsecrets.yaml',
     'ECommerce.DatabaseMigrator/k8s/migrate-job.yaml',
+    'EcommerceApp/k8s/servicemonitor.yaml',
 ])
 
 # Use kustomize for AdminUI
@@ -38,19 +39,21 @@ k8s_yaml(kustomize('ECommerce.AdminUI/k8s/overlays/dev'))
 k8s_resource(
     'modularmonolith',  # This should match the name in your deployment.yaml
     port_forwards=['8080:8080'],
-    labels=["app"]
+    labels=["app"],
+    trigger_mode=TRIGGER_MODE_MANUAL
 )
 
 k8s_resource(
-    'dev-admin-ui',  # Updated to match the namePrefix in kustomize
+    'admin-ui', 
     port_forwards=['8081:8080'],
     labels=["app"],
     trigger_mode=TRIGGER_MODE_MANUAL
 )
 
 k8s_resource(
     'db-migrator',  # This should match the name in migrate-job.yaml
-    labels=["migrations"]
+    labels=["migrations"],
+    trigger_mode=TRIGGER_MODE_MANUAL
 )
 
 # Enable file watching for live updates